1 /* 2 * Copyright (c) 2007, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package com.sun.media.sound; 27 28 /** 29 * A resampler that uses third-order (cubic) interpolation. 30 * 31 * @author Karl Helgason 32 */ 33 public final class SoftCubicResampler extends SoftAbstractResampler { 34 35 @Override getPadding()36 public int getPadding() { 37 return 3; 38 } 39 40 @Override interpolate(float[] in, float[] in_offset, float in_end, float[] startpitch, float pitchstep, float[] out, int[] out_offset, int out_end)41 public void interpolate(float[] in, float[] in_offset, float in_end, 42 float[] startpitch, float pitchstep, float[] out, int[] out_offset, 43 int out_end) { 44 float pitch = startpitch[0]; 45 float ix = in_offset[0]; 46 int ox = out_offset[0]; 47 float ix_end = in_end; 48 int ox_end = out_end; 49 if (pitchstep == 0) { 50 while (ix < ix_end && ox < ox_end) { 51 int iix = (int) ix; 52 float fix = ix - iix; 53 float y0 = in[iix - 1]; 54 float y1 = in[iix]; 55 float y2 = in[iix + 1]; 56 float y3 = in[iix + 2]; 57 float a0 = y3 - y2 + y1 - y0; 58 float a1 = y0 - y1 - a0; 59 float a2 = y2 - y0; 60 float a3 = y1; 61 //float fix2 = fix * fix; 62 //out[ox++] = (a0 * fix + a1) * fix2 + (a2 * fix + a3); 63 out[ox++] = ((a0 * fix + a1) * fix + a2) * fix + a3; 64 ix += pitch; 65 } 66 } else { 67 while (ix < ix_end && ox < ox_end) { 68 int iix = (int) ix; 69 float fix = ix - iix; 70 float y0 = in[iix - 1]; 71 float y1 = in[iix]; 72 float y2 = in[iix + 1]; 73 float y3 = in[iix + 2]; 74 float a0 = y3 - y2 + y1 - y0; 75 float a1 = y0 - y1 - a0; 76 float a2 = y2 - y0; 77 float a3 = y1; 78 //float fix2 = fix * fix; 79 //out[ox++] = (a0 * fix + a1) * fix2 + (a2 * fix + a3); 80 out[ox++] = ((a0 * fix + a1) * fix + a2) * fix + a3; 81 ix += pitch; 82 pitch += pitchstep; 83 } 84 } 85 in_offset[0] = ix; 86 out_offset[0] = ox; 87 startpitch[0] = pitch; 88 89 } 90 } 91